Cryogenic cooling system and an insert therefor

Abstract

A cryogenic cooling system is provided comprising a primary insert (118) and a demountable secondary insert (128). The primary insert (118) comprises a plurality of primary plates (111, 112), each primary plate having a primary contact surface, and one or more primary connecting members (117) arranged so as to connect the plurality of primary plates (111, 112). The demountable secondary insert (128) comprises a plurality of secondary plates (121, 122), each secondary plate having a secondary contact surface, and one or more secondary connecting members (127) arranged so as to connect the plurality of secondary plates (121, 122) such that the secondary insert (128) is self-supporting. One or more adjustment members are configured such that, when the secondary insert (128) is mounted to the primary insert (118), the adjustment members cause the primary and secondary contact surfaces of the respective primary (111, 112) and secondary plates (121, 122) to be brought into conductive thermal contact.

1 . A cryogenic cooling system comprising:
 a primary insert comprising:
 a plurality of primary plates, each primary plate having a primary contact surface; and 
 one or more primary connecting members arranged so as to connect the plurality of primary plates; 
   a demountable secondary insert comprising:
 a plurality of secondary plates, each secondary plate having a secondary contact surface; and 
 one or more secondary connecting members arranged so as to connect the plurality of secondary plates such that the secondary insert is self-supporting; and 
   one or more adjustment members;   wherein the one or more adjustment members are configured such that, when the secondary insert is mounted to the primary insert, the adjustment members cause the primary and secondary contact surfaces of the respective primary and secondary plates to be brought into conductive thermal contact.   
     
     
         2 . A system according to  claim 1 , wherein the one or more adjustment members form part of one or both of the primary insert and the secondary insert. 
     
     
         3 . A system according to  claim 1 , wherein the said conductive thermal contact is provided by area contact between conformal planar regions of the respective primary and secondary contact surfaces. 
     
     
         4 . A system according to  claim 1 , wherein the one or more adjustment members are configured to accommodate a misalignment between each of the plurality of secondary plates of the demountable secondary insert and the corresponding primary plate of the primary insert. 
     
     
         5 . (canceled) 
     
     
         6 . A system according to  claim 4 , wherein when the secondary insert is in a demounted state, the secondary plates are spatially positioned with respect to one another in a secondary configuration, and the primary plates of the primary insert are spatially positioned with respect to one another in a primary configuration; and wherein the misalignment is the offset between the plane of a secondary plate and the plane of the corresponding primary plate in the respective primary and secondary configurations. 
     
     
         7 . A system according to  claim 6 , wherein the respective primary and secondary configurations are maintained when the demountable secondary insert is in a mounted state. 
     
     
         8 . A system according to  claim 1 , wherein operation of the adjustment member does not change the separation between adjacent primary plates of the primary insert or adjacent secondary plates of the secondary insert. 
     
     
         9 . A system according to  claim 1 , wherein the one or more adjustment members comprise one or more deformable members forming part of a respective primary plate or secondary plate. 
     
     
         10 . A system according to  claim 6 , wherein the one or more adjustment members cause one or both of the primary or secondary configurations to be adjustable so as to cause the conductive thermal contact. 
     
     
         11 . A system according to  claim 1 , wherein the one or more adjustment members are configured to change the separation between adjacent primary plates or adjacent secondary plates. 
     
     
         12 . A system according to  claim 11 , wherein the one or more adjustment members form at least part of one or more of the primary connecting members or secondary connecting members. 
     
     
         13 . A system according to  claim 11 , wherein the one or more adjustment members is configured to allow movement of the one or more primary plates with respect to the one or more said primary connecting members. 
     
     
         14 . (canceled) 
     
     
         15 . A system according to  claim 11 , wherein the one or more adjustment members is configured to allow movement of the one or more secondary plates with respect to the one or more said secondary connecting members. 
     
     
         16 . (canceled) 
     
     
         17 . A system according to  claim 11 , wherein the primary or secondary connecting members are rotatable so as to change the separation between adjacent primary plates or adjacent secondary plates using the one or more adjustment members. 
     
     
         18 . A system according to  claim 11 , wherein the one or more adjustment members form respective flexible portions of the primary or secondary connecting members. 
     
     
         19 . A system according to  claim 1 , wherein one or more of the plurality of secondary plates is configured to accommodate experimental apparatus. 
     
     
         20 . A system according to  claim 1 , wherein the primary insert comprises a dilution refrigerator, a helium-3 refrigerator, or a 1 kelvin pot. 
     
     
         21 . A system according to  claim 1 , wherein one or more of the secondary connecting members are removable such that two or more of the plurality of secondary plates can be detached from the demountable secondary insert as a unitary, self-supporting assembly. 
     
     
         22 . A demountable secondary insert for use in a cryogenic cooling system according to  claim 1 . 
     
     
         23 . A method of operating the system of  claim 1 , wherein the demountable secondary insert comprises a first secondary plate, a second secondary plate and a third secondary plate, a first secondary connecting member connecting the first secondary plate to the second secondary plate, and a second secondary connecting member connecting the second secondary plate to the third secondary plate, and wherein the primary insert comprises three primary plates, each said primary plate corresponding to a respective secondary plate of the secondary insert, the method comprising:
 mounting the secondary insert to the primary insert such that secondary plates are conductively thermally coupled to the corresponding primary plates using the one or more adjustment members; and   partially demounting the secondary insert from the primary insert, wherein partially demounting the secondary insert comprises:
 removing the first secondary connecting member from the secondary insert; and 
 removing the second secondary plate, the third secondary plate and the second secondary connecting member from the primary insert as a unitary self-supporting assembly, without removing the first secondary plate from the corresponding plate of the primary insert.